HINTS AND CONJECTURES. 309 



regard to the nature of our rocks, and the cncumstances of their 

 formation. We have found, that the strata have been deposited by 

 water, and were originally nearly horizontal ; that through some power- 

 ful agency, they have suffered great changes, in numerous breaks and 

 denudations, by which valleys and water-courses have been formed ; 

 that the different beds are not continued round the globe, nor overall 

 Britain, but wear out successively to thin edges, so that we cannot 

 arrange them into any regular or constant series ; that some beds, or 

 poi'tions of the strata, pass into others, and some are secretions from 

 others ; that the strata have not been formed by the gradual deposition 

 of sediment, such as is now deposited in the bottom of the ocean ; 

 that the difference between the strata, in point of hardness, and in the 

 nature and quantity of their organic remains, is not according to 

 the order of their succession ; that they have not been produced by 

 alternate depositions from salt water and fresh, nor by successive 

 creations, or formations, separated by ages or long intervals, and 

 distinguished by peculiar animals or vegetables, but appear to 

 have been formed nearly about the same period ; and that volcanic 

 agency, having produced the whinstone dykes, may have been em- 

 ployed in raising the strata, and may have caused some of the breaks 

 in them.— It now remains to be inquired, at what period, and in what 

 manner, the strata may have been deposited. 



It is a fashionable opinion among geologists, that all tlie strata* 

 including even a great part of the alluvial beds, were deposited before 

 the creation of man ; and some of the most respectable geological 

 writers have attempted to reconcile the formation system with the 

 Mosaic account of the creation, by supposing that the six days of the 

 creation are six indefinite periods, of great length, corresponding with 

 the eras of the different formations. Such writers fancy, that they 

 have discovered a coincidence between the order in which organized 

 bodies occur in the strata, and the order of the creation of vegetables 



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